In the surgical repair of soft tissue, such as, for example, the surgical reattachment of a torn ligament to bone, it is known to use multi-part devices to fix the soft tissue to the bone. The multi-part devices typically include a screw or other bone anchoring device, and a button-like device for anchoring the suture therein. The anchor is installed in a predrilled hole in the bone, and the soft tissue is fixed to the anchor in the bone with sutures, which are fastened together with the button instead of with knots.
A disadvantage of such devices is that the quality and strength of the device may be limited by the quality and strength of the suture, and/or by the integrity of the attachment of the device to the bone. The soft tissue will detach from the anchor in the bone if the suture slips or breaks. If the anchor or the button slips or becomes dislodged, the soft tissue will not remain anchored to the bone.
Another disadvantage of such a device is its multi-part nature. It is difficult to join the button and the anchor with a suture and maintain the button appropriately oriented with respect to the anchor and to the tissue while the suture is appropriately tensioned and fastened in situ.
U.S. Pat. No. 5,413,585 to Pagedas discloses a self-locking suture which includes a suture lock crimped onto a suture thread. The suture lock admits a suture in one direction only and does not permit withdrawal of the suture from it. No knots are required in the suture, as it forms a locked stitch. In addition, the suture can be tensioned and the locked stitch formed by a single pair of hands in a simplified operation.
The Pagedas self-locking suture relies on a mechanical locking device to form the locked stitch. It is therefore relatively complex and is subject to breakage and slippage.
It would be an advantage to provide a surgical soft tissue fixation device which overcomes the disadvantages of the prior art devices.